1. Field of the Invention
The subject matter of this invention relates to a syringe designed to contain two different liquid mediums and then permit the injection of the two different mediums sequentially into an IV line or a needle into a patient.
2. Description of the Related Art
Syringes are commonly used to inject medicine and saline solutions into a human or an animal. These injections usually occur by means of an IV (intervenous) line or needle which is connected into the body of the human or animal. Usually, the injected liquid that is contained within the syringe comprises a single liquid or a mixture of liquids. The syringe usually comprises a single internal compartment and has a single needle. Sometimes, the injection of medication requires the insertion of two different liquids. For example, there is a procedure that is known as a saline/heparin push. It is absolutely necessary that the saline be injected prior to the heparin because if the reverse occurs the IV line or needle will become immediately clogged requiring the IV line or needle to be removed and then reinstalled in position within the patient. Each removal and reinstallation is painful to the patient, time consuming to the doctor and nurse and costly to the medical facility not only in the extra time involved but because additional catheters, IV lines and syringes are required. Every year within the United States, there are literally billions of saline/heparin pushes administered. This means that every year there is a large number of mistakes that are made. At the current time, the heparin is contained within a syringe and the saline is contained within a separate syringe. Both syringes are essentially identical in size, quantity of liquid and color with the exception that one refers to heparin and the other refers to saline. It is relatively easy for the nurse to pick up the heparin syringe and administer that prior to administering of the saline.
The current practice includes an irrigation or cleansing flush consisting of a predetermined volume of saline (0.9 percent sodium chloride) delivered through a syringe. This is done to cleanse the inner lumen of the catheter of blood, medication or particulate matter. The saline flush is followed by an installation of heparin, via a syringe, to prevent occlusions (from blood or fibrin)n within the inner catheter lumen.
The Intravenous Nursing Society (INS) states that the volume of the flush should be equal to the priming volume of the catheter, plus any add-on pieces (i.e. extension sets) times two. This means that the volumes of the saline and heparin flushes could be identical. Medication errors frequently occur when the clinician or person delivering the flush confuses the two syringes and delivers the heparin flush first, followed by the saline flush. When this occurs, there is the increased potential of catheter occlusion if blood were to reflux into the distal catheter tip, since saline has no anticoagulant properties.
It would be desirable to utilize a single syringe which includes both the heparin and the saline where it is automatic that when making of the injection that the saline will be administered first and then the heparin will follow. In the past, there have been constructed multi-chamber syringes which are designed to accomplish this automatic sequential delivery of two different liquids. However, in the past, the sequential delivery syringes had to be prefilled and then be sterilized. The particular liquid in the syringe may be affected negatively by the sterilization procedure, which is usually radiation or heat. Therefore, at times it would be necessary to sterilize a sequential delivery syringe that contains only one of the liquids and then have some way to insert the second liquid into the syringe after the sterilization. It is believed that prior to the present invention there has not been known to utilize a novel sterile approach to the insertion of the second solution when constructing such a syringe.
Additionally, such a sequential delivery syringe could be used to deliver a medicament, such as an antibiotic followed by a quantity of saline. It would be desirable to construct a sequential delivery syringe that could be supplied to the physician or nurse that could be used to remove a precise quantity of medicament necessary for the particular patient and then administer that medicament and follow it with the saline solution.
The basic embodiment of the present invention comprises a sequential delivery syringe which has a body which includes an internal chamber. The body is substantially closed at one end but still provides access into an internal chamber through a through passage. The opposite end of the body is totally open. A luer is connected to the syringe at the one end with the luer including a discharge passage. The luer also includes a piercing member which extends within the internal chamber. A mid-piston is movably mounted within the internal chamber of the syringe with the mid-piston dividing the internal chamber into a front section and a rear section. A stopper piston, which is mounted on a plunger, is mounted in the rear section with this plunger extending exteriorly of the body of the piston. Also mounted within the rear section is a means for collapsing with the first liquid to be contained within this means. This means is normally closed. A second liquid is to be contained within the front section of the internal chamber. Upon movement of the plunger and the stopper piston toward the one end the second liquid is to be discharged through the discharge passage until the mid-piston is penetrated by the piercing member which provides access into the means for collapsing and permit the first liquid contained therein to be discharged through the discharge passage.
A further embodiment of the present invention is where the first basic embodiment is modified by the one end of the syringe body having a luer lock comprising a collar which surrounds an internal annular chamber and there is a tapered male luer centrally mounted within this annular chamber. It is the tapered female luer that is attached directly to the syringe.
A further embodiment of the present invention is where the previous embodiment is modified by the collar not having just a single opening through which to conduct the liquid into the discharge passage but there is actually a plurality of openings.
A further embodiment of the present invention is where the plurality of openings are located about the piercing member.
A further embodiment of the present invention is where the first basic embodiment is modified by the stopper piston including an air discharge valve.
A further embodiment of the present invention is where the first basic embodiment is modified by the means for collapsing comprising a flexible walled bag.
A further embodiment of the present invention is where the first basic embodiment is modified by the means for collapsing comprising a bellows.
A further embodiment of the present invention is where the first basic embodiment is modified by the piercing member being fixed to said body by being press fitted into a discharge passage formed within one end of the body.
A further embodiment of the present invention is where the first basic embodiment is modified by the piercing member being hollow having a circular sidewall with an opening formed in the sidewall spaced from the open end of outer end of the piercing member.
A further embodiment of the present invention is where the first basic embodiment is modified by the piercing member being hollow defined by a circular sidewall and an elongated slot is formed in the sidewall extending from the open outer end of the piercing member.
A further embodiment of the present invention is where the first basic embodiment is modified by the piercing member being mounted on a mounting disc with this mounting disc being placeable within the internal chamber of the body and being positioned directly adjacent the substantially closed one end of the body.
A further embodiment of the present invention is where the first basic embodiment is modified by the piercing member being mounted entirely through the mounting disc to be projected from both the front side and the back side of the mounting disc.
A second basic embodiment of the present invention comprises an integral one-piece syringe luer lock which is constructed to include a collar which has an internal chamber which is internally screw threaded. This collar is to facilitate, by the threads, attachment to an appropriate connector for discharge of the liquid into an IV line or needle which is connected to a patient. A male/female luer is mounted within the internal chamber with this male/female luer having a discharge passage, and it is through this passage that the injectable liquid is to be conducted. At least one opening is formed within the collar which connects to the internal chamber. A piercing member is mounted on the collar directly adjacent this opening. A female luer surrounds a portion of the piercing member with this female luer being mounted on the collar whereby a syringe liquid discharge tube is to be inserted within the female luer in a liquid-tight manner with the piercing member to then be located within the internal chamber of the syringe so as to penetrate a movable piston within the internal chamber of the syringe.
A further embodiment of the present invention is where the second basic embodiment is modified by the male/female luer being centrally mounted within the internal chamber.
A further embodiment of the present invention is where the second basic embodiment is modified by there being not just a single opening but a plurality of openings formed within the collar.
A further embodiment of the present invention is where the second basic embodiment is modified by the plurality of openings defined as being located about the piercing member.
A further embodiment of the present invention is where the second basic embodiment is modified by the piercing member being pressed fitted into said one end.
A further embodiment of the present invention is where the second basic embodiment is modified by the piercing member being hollow and having a circular sidewall, an opening formed within said sidewall spaced from the open outer end of the piercing member, said second liquid to be able to be conducted through said opening substantially emptying said internal chamber of said second liquid.
A further embodiment of the present invention is where the second basic embodiment is modified by the piercing member being hollow and having a circular sidewall, an elongated longitudinal slot formed in said sidewall extending from an open outer end of said piercing member.
A further embodiment of the present invention is where the second basic embodiment is modified by the piercing member being mounted on a mounting disc, said mounting disc being placeable within said internal chamber and being located directly adjacent said one end.
A further embodiment of the present invention is where the second basic embodiment is modified by the piercing member extending entirely through said mounting disc.